Characteristics and environmental risks of heavy metal contents in microplastic particles from plastic flooring and shoe soles
The widespread use of plastic products has led to the extensive microplastic pollution of the environment.Microplastic particles(MPs)not only serve as contaminants widely distributed in the environment but also carry heavy metals,increasing risks to ecosystems and human health.In this study,we investigated the heavy metal pollution characteristics of MPs produced from various types of plastic ground and shoe soles.Samples of MPs were collected by simulating the physical wear processes of plastic cement flooring and shoe soles.The contents of typical heavy metals(Cd,Cr,Cu,Mn,Ni,Pb,Zn)were analyzed.The order of total heavy metal content was shoe soles(labor protective shoes>sports shoes>daily life shoes)>plastic flooring(indoor>outdoor).The concentrations of Cr(68.7 mg/kg)and Pb(346 mg/kg)in MPs are highest from sports shoes;Cu(136 mg/kg)and Zn(2 407 mg/kg)show the highest concentration in MPs from work protective shoes;Mn(26.8 mg/kg)exhibits the highest concentration in MPs from outdoor plastic flooring;Ni(1.00 mg/kg)and Cd(22.7 mg/kg)are most abundant in MPs from indoor plastic flooring.Compared with other heavy metals,the content of Zn in various types of MPs is the highest.Current study discussed the migration and accumulation behavior of these MPs in indoor and outdoor environments,evaluated their potential risks to ecosystems and human health,and provided scientific basis for the formulation of targeted pollution prevention and control measures.
Plastic wear particlesmicroplastics(MPs)heavy metal pollutionecological riskshuman health risks